Brad Pitt is expected to hit New York Monday to pump his latest film, “Killing Them Softly.” The star, who plays a contract killer in the movie, will hit a downtown screening and party where, we hear, guests will include Pitt’s co-stars James Gandolfini and Ray Liotta. The Andrew Dominik-directed movie, in which Pitt investigates a heist that took place during a high-stakes, mob-protected poker game, is based on George V. Higgins’ 1974 novel “Cogan’s Trade.” It opens Nov. 30.